November 6, 2012

The Art And Science Of Beer Foam

by Michael Harper

You wouldn’t know it by looking at them, but Brewers (that being, brewers of beer) are scientists of a sort. Beer is often associated with a sloppy sort of inebriation, the kind of buzz that makes the room spin around. It’s a rough and ready brew, and as such, it’s easy to see the crafters of this beverage to be something of a rowdy bunch. They’re beards and general large stature only help to further this preconception.

It might surprise you, then, to know bringing a tasty beer to life isn’t only an art, it’s a tedious science with formulas and experimentation and even mutation involved.

Take, for instance, the foamy head which sits atop your favorite amber ale. This topping is a suitable crown for any good beer, providing not only ample aesthetics, but also locking in some of the key aromas in the brew; yeasty, fruity, hoppy, all the flavor characteristics which define the beer’s unique personality.

Tiny, carbon dioxide filled bubbles and microbubbles comprise this foam, providing a tall and thick foam for ales and “lighter” beers, a smooth, creamy foam for stouts and “darker” beers.

These bubbles are stabilized and supported on top of the beer by proteins from the yeast which prevent the foam from dissolving into the beer too quickly.

Though brewers and their scientist peers understood how the foam ended up on top of the beer, they had yet to identify which part of the protein was responsible for lifting the foam up by its shoulders and keep it from dissolving into the alcoholic depths.

In a new study published in the ACS’ Journal of Agricultural and Food Chemisty, researcher Tomás G. Villa and colleagues have said they’ve discovered this specific foam-making gene. In fact, this gene is similar to other yeast genes found in other alcoholic beverages, such as wine and sake. Villa and his team are calling this newly discovered gene CFG1 and are suggesting that, with this discovery, there might even be some good beer ahead.

“Taken together all the results shown in the present paper make CFG1 gene a good candidate to improve the foam character in the brewing industry,” write the researchers in their paper.

With better foam character, future beers may have a prolonged aroma, tickling mustaches even further with scents of hops, yeast and grain. All that remains is for these brewers to take advantage of this new gene and begin brewing it into their beer. This might be easier said than done, however, as foam is already a natural occurrence in beer. As such, members of the blossoming community of craft brewers already take pride in the head which sits atop their flagship beers. No, this kind of experimentation will likely be used by the big guys in order make their beers look more appealing to those drinkers who may prefer a locally brewer craft beer ass opposed to something from those other guys.

Either way, better beer is better beer, and for this the heavens should be thanked.